How to manage extra or spot channels in FileMan?

The following settings are available in CalderaRIP from version 12.1 onwards.

CalderaRIP's FileManager allows you to customize the processing and rasterization of image files, in particular with spot and alpha channels. This article guides you through the process.

Spot Channels in TIFF

These settings are particularly important for users working with Photoshop files (.PSD) and certain TIFF files generated by specific drivers, such as Durst drivers. It allows you to invert your spot channels when necessary.

Spot channel inversion involves reversing the grayscale values in a spot channel. In a TIFF file, each spot channel typically contains a grayscale image, where varying shades of gray represent different ink levels. Inversion alters the areas where the spot color is applied.

For example:

• A value of 0 (black) indicates full application of the spot color.
• A value of 255 (white) indicates no application of the spot color.

When you invert a spot channel:

• Black (full application) becomes white (no application).
• White (no application) becomes black (full application).

In some cases, inverting your spot channel is necessary to ensure the color or effect is applied correctly. For instance, if a TIFF file was created in one software with specific spot channel values, another application may require an inverted version to maintain consistent output.

How to do it?

1. Open CalderaRIP.
2. To launch FileMan, double-click its icon or drag and drop an image on it:
   
3. Click on the Setup button.
4. Go to the Misc tab.
5. Go to the “Spot Channels in TIFF” area:
   • In the "Invert when opening" setting, there is an "Auto" option, which is set by default. With this option set, Adobe Photoshop files and certain TIFF files generated by our drivers (e.g., Durst drivers) will be inverted, while all other files will remain unchanged:
     
   • You can also choose whether to force inversion when opening or saving the file by choosing the "Yes" option, or to disable inversion by selecting the "No" option.

Alpha-Channels Options

In this area, you can use the alpha channels from your PNG, PSD, or TIFF files to simplify the import process in CalderaRIP.

The options to copy an alpha channel to a spot channel and delete it afterward help save time by automatically transferring transparency information.

This feature is useful for ensuring that specific areas are defined for spot color application, making it easier to work with complex designs and maintain consistency across projects.

How to do it?

1. Open CalderaRIP.
2. To launch FileMan, double-click its icon or drag and drop an image on it:
   
3. Click on the Setup button.
4. Go to the Misc tab.
5. Go to the “Alpha-Channels Options” area:
   • Copy Alpha-Channel to Spot Channel: Check this option to copy the alpha channel to the spot channel, with a dropdown menu to select from the detected spot colors in the file.

       Info

     This option "forces" the alpha channels of files to be assigned to the selected spot channel (such as white, as shown in the following example). This is particularly useful for saving time, as it allows the Automatic separation method (Print module > Page Setup > Spot ink tab) to function without requiring further setup.

     
   • Delete Alpha-Channel After Copy: Enable this option to remove the alpha channel once it has been copied to the spot channel.